From BlenderWiki
Hi Egan, thanks for having a try with the J stuff in the Render Window :) But I'm not sure the description you use isn't a bit confusing ... at least the part where you describe to press J between the 1. and the 2. render (which isn't necessary) and the part: "The key is to "fill" the empty buffer with the new render, even though it is labeled as previous."
My suspicion is that there are always two render buffers and only the "current" one is directly rendered to - the second one ("previous") is copied from the "current" one before that gets changed.
You can check this easily by rendering 2 different images right after each other and then press J (which seems to simply toggle between the display of the 2 buffers) :)
Ideas?
--Hoehrer 08:38, 4 January 2008 (CET)
When I try to do it as you say, the first rendering disappears, and when I press J, the 'Previous' buffer is empty. This is true when I close, hide, or minimize the render window between the two renderings.
I did notice an error I made in my instructions, it does not work when you minimize the window; rather, you have to send it to the background Esc
Step by step instructions are:
- Press Render or F12
- Press J to show the empty buffer (the one we want to "fill" with the new image)
- Send the window to the background by pressing Esc. Do not close, or minimize it!
- Make your changes.
- Render again.
- Press J to switch between the two renderings.
I have already revised that section.
--Egan 18:10, 4 January 2008 (CET)
The funny thing is I can reproduce the things you mention on my Linux machine now (the tests I made were on a Windows machine at work and there the "previous" buffer seems to work anytime).
So I agree that this is the best version of the text for now because it'll work everywhere, but I suspect this may even be a bug in Blender. I'll make more tests on Windows on monday to make sure I didn't screw up something ;)
What system do you use?
--Hoehrer 11:07, 5 January 2008 (CET)
Render Window Buffers
I totally agree that the method is very convoluted, perhaps it is actually a bug in Blender. It makes much more sense to have it automatically use both buffers, and that would be way less confusing.
I am using XP Home SP2
--Egan 17:11, 5 January 2008 (CET)
